- * @param lon current longitude
- * @param lat current latitude
- * @param root root path point to data file location (timezone, etc.) */
- SGTime( double lon, double lat, const string& root );
+ * @param lon_rad current longitude (radians)
+ * @param lat_rad current latitude (radians)
+ * @param root root path point to data file location (timezone, etc.)
+ * @param init_time provide an initialization time, 0 means use
+ current clock time */
+ SGTime( const SGGeod& location, const SGPath& root,
+ time_t init_time );